Hey Jb2! Good job on these, really great work being on the grind and tackling these concepts. You're definitely getting the hang of them. When you say "move onto other fundamentals", fundamentals aren't really something you move on from. It's something you're always studying, no matter how pro you are. In terms of these drawings, I'd say that you're getting the idea but it looks like you're trying to jam everything in all at once. You should be focusing on trying to simplify your drawings, for example the action of what the pose is doing is lost in these drawings. At this stage in a drawing you should only be using C S or I lines. Those are lines that explain what the body is doing, not the contour. If you don't know the distinction, I'd highly recommend watching @Stan Prokopenko's video Q&A – Gesture vs Contour and Scribbly Lines. Hope this helps!

Very good I think for your gesture Drawing, at the beginning try to draw with shoulder and focus more on the movement rather than details. Sometimes your lines feels broken probably because of doubt or hesitation. The Construction part with your boxes feel off in space. Besides that it's good you try things rather being afraid